The actor, known for diving headlong into his roles, puts his emotional stamp on 'Blue Valentine' and contemplates what's next. 'I don't want to play the same note,' Gosling says.

Although "Blue Valentine" is a prototypically independent movie — a budget of just over $1 million, more than 60 screenplay drafts — it has managed, like much of Gosling's work, to achieve a pop-cultural and critical heft that exceeds its evident commercial potential. A hit at the 2010 Sundance and Cannes film festivals, the movie briefly became a culture war flashpoint when the Motion Picture Assn. of America gave it an NC-17 rating for a scene in which Dean performs oral sex on Cindy. (The rating was later changed to an R on appeal.)

Much of the film's buzz centers on its emotional grittiness, which arose in part from an extensive amount of preparation by Gosling and Williams. Cianfrance, a filmmaker with a fastidious, perfectionist streak, had the pair live together in the same house as they honed their characters. They walked their dog, cooked and made home videos, all to create a more plausible marital environment (that they could then puncture in the film). Since Dean works as a mover, Gosling got hired by a moving company. Cianfrance said he expected him to carry a few boxes and call it quits; Gosling bonded with the movers and worked all day.

A willingness to plunge in headlong is a Gosling trademark. "Ryan doesn't really know how to ride a skateboard," Cianfrance says, describing his star's persistence. "But he doesn't know that. So it's fun to watch him try to do a trick."

If the actor has a serious, save-the-world side — he recently returned from the Congo, where he shot documentary shorts for the storytelling website MediaStorm.com — Gosling's default mode is that of the wiseguy, often of the schoolboy sort. He is late for the interview because, he says, he ran into Andy Garcia, who talked his ear off, but how much of that is true is impossible to tell. He's prone to baiting his producers and directors by making fun of everything from their e-mail sign-offs to their cooking quirks. He wears a kind of perma-smirk that makes him look perpetually amused by his surroundings.

And he takes manifest joy in telling a story about the specific ways Cianfrance wanted him to walk the dog that he and Williams pretended to own, particularly how he repeatedly rubbed its stomach so that it would relieve itself on said walk.

He turns serious, however, when discussing his acting motivations. "I don't really like doing interviews because I don't have any answers about why I act," he says. "It's like a compulsion. It's people who eat and eat and eat and they don't know why and they keep getting fatter but they can't stop. It's like that.... And then you find yourself on a set throwing yourself off a bridge, and you're asking yourself, 'Why am I doing this?' And I don't know."

Director Andrew Jarecki, who worked with Gosling on his recent "All Good Things," says that while the actor's motivations may be instinctual, Gosling brings an uncommonly analytical approach to a set. Unlike many actors, Gosling will watch himself on a monitor between takes and keep a director off-balance by trying wildly different interpretations of the same scene, offering opinions as he goes.

He is, Jarecki says, the kind of outspoken actor who wants to have a key voice in the process, which may explain why he leans so heavily away from studio roles and their filmmaking-by-committee ways. The actor told Jarecki he wouldn't want to make a movie in which the entire crew couldn't fit into a single bus. "Ryan wants a direct line to the director. He's not the kind of guy who wants to get a memo from a studio executive," Jarecki says.

In "All Good Things," Gosling plays a thinly veiled version of New York real estate scion Robert Durst. The movie, which like "Blue Valentine" centers on a troubled marriage, costars Kirsten Dunst and hit theaters just a few weeks ago after a cloud of release uncertainty.

Annoyed by the timing, Gosling isn't promoting the film. "I try not to make too many movies," he says. "I get sick of myself, so I can imagine how everyone else feels. And for the two to come out at the same time, it makes me feel sick."

There has also been chatter that Gosling clashed with Jarecki during production. The director demurs, saying he "welcomed all the thoughts that Ryan brought to the set."

Asked if he's proud of the film, Gosling hesitates. "I'm proud of what Kirsten does in the movie," he says finally. (He later elaborates: "It was a hard film to make because it was such a dark experience. Just the story itself, trying to understand the things that your gut tells you you don't want to feel for this person. It's an interesting experience to have, but you're happy when it's over.")